The cold grip of the smoke did little to surprise Heather compared to the shock she had at the magic draining properties of it. It felt as if her very life was being sapped away which, by some properties, it was. She immediately knew that she had chosen the wrong option—that she should have ran away, and as fast as she could at that.
Just holding up the quickly strengthening beast was enough of a magical strain, but the smoke was diminishing her powers at a rapid rate. She let go of her mental grasp of the creature, using all the strength she could muster to push it away from her. Then she turned to run from the smoke, the beast, and the unknown, but it was already too late.
She only made it a few steps before her legs gave away and she collapsed.